Drafting machine



NOV 27, 1951 c. H, LITTLE ETAL,

DRAFTING MACHINE Original Filed Sept. 22, 1944 Patented Nov. 27, 1.951v

'DRAFT-ING MACHINE Charles Henry Little, Cleveland Heights, and CharlesHubbard Little, Cleveland, Ohio; Nan 'Hubbard Little, executrixof's'aidCharles'Henry Little, deceased, assignorsyby direct andvmes'neassignments, to V-Universal Drafting MachineA vCorporation,Cleveland,Ohio, a corporation of Ohio Original application September 22,1944,lSerial N0. 555,267. ,'Divided and 'this 42111i'plliit'til'nN0` vembel'28, '1945, Serial N o. :631,334

1,2 claims. (o1. 33-79) The present invention relates todrafting -ma-'chines anclsimilar devices comprising alparallel `motionmechanism'or'arm, one end'of which is adapted to *fbe secured toa-table,drafting 'board or like 'device affording a working-surface,-over 'whichthe'otherend of vthe arm, provided lwith "some suitable draftinginstrument or the like,is

adapted-to 'be `movedand-the `instrumentcarried thereby maintainedparallel in successive positions. AParallelnrl'otion mechanismsaregenerally considered tobe eithercf the so-called parallelogram type orof lthe-so-L-called wheeland band type, depending uponwhetherthesectionor sections thereof are Vessentially members arrangedin parallel'ogram 'fashion 'and pivoted together adjacentto'th'e'cornerscr wheels held inspaced relation bystrut-like imembersand encircled vby a band or bands'which maintain a predetermined angularrelationship therebetween.

The present invention relates to parallel motion mechanisms and morespecifically' to `a drafting 'machine or the' like comprisingaparallelmo- "'tion'mechanism ofthe Wheel andba'nd type-andoneoftheprincipal objects is the provisionbf a novelandimproved draftingmachine or similar device soconstructedand arranged 'that lit -willbe'accurate inoperation andwill not 'have the appearancefof being bulkyandun'gainly, andin 4which the l'hands `and Wheels are completelyfenclosed.

Another 'object ofthe inventionis v`the provision of'a novel andimproved' drafting machine crithe like'of-the character'referred' toVhaving alstrutor struts enclosing the -wheelsand band or bandsand vsoconstructed and `arranged as to vbe extremely Vrigid thoughcomparatively light in Weigh-t Jand adjustable'in length for'the purposeof tighteningor lloosening the'band.

Another object of the invention is Vthe yprovi sion Ycfa novel andimproveddrafting machine or the like of=the characterreferred-tohaving-a strut or struts enclosing the wheels-anduband or -bandsandsoconstructed and arrangedras-to be i-readilypartially disassembledtofafford access to the ends canl bev readily-connected or disconnectedandfat least one end will be of minimum thicknv .f2 ness andmaximumhexibility 4so thatzthe band can be lthreaded .aroundthefassembled wheels `although fthe enclosing strut kor member .conformsy closelyA to -thef circumference-thereof :so;as;to' \pro duce Vasection lof minimum Aoverall ywidth for wheels-of"anygivenfsize.

'Another `objecto`f the invention is ethe f provisionof a novel andimproved-separable geband Afor a wheel Y and Yband itypefdraftingmachine:or fthe like, whichfband comprises-means forureadilyde- Aitzw-hably"securing `the i'lends thereof together and has at least one end thereofof minimumthickness and maximum flexibility consistent with other-requirerhents @so that it :can be threaded around assembled Wheelslalthcnigh the f enclosing stru-t or'membe'r con-iormscloselyftothefcircumference of the wheels.

The invention resides in certainconstructions andcombinations*-andarrangementsf ofi-parts and further objects andadvantages -Wlllbe apparent to thosesklledi in {the'L art@ to which theAinvention `relates'froin the -follov'vng 'descriptionvof the preferredembodiment described 'with 'reference vto the accompanying drawingsiforming a -part of 'this-specication--n whichsimilar-referencecharactors designate cor'respending parts, and -inwhich Y Fig. l aplanview of a draftingmachine'embodyingthe presentinvention;

Fig. 2 is a fragmentary pian view foffa'fp'ortion of the'draftingmachine showninFigl;

Fig. 3 is a sectional view, Vwith portions "in elevation, approximatelyvo'nthe line i3-L3, 'i'gfQ and Fig. 4 is ai'fragmentary View ofthe bandernployed in the drafting machine s'hown'in'ilgfl.

Referring to the drawings, 'the drafting lmachine `snol/vn therein'comprises a vtvv'section .parallel motion-mechanism or arm of the wheelandl band type vhaving one end detachably .connected'to a drawing'boardandthe other or free end provided withaprotractor 'head adapted to bemoved aboutthe drawingboard. rIhefparallel motion mechanism or armcomprises'two angularly movable sections, each 'comprising apair ofWheels of 'equal diameter encircled by afle'zible ban'd, which VWheelsa'reheld in vspaced ie'iation by a strut or strut member enclosing thesame and the bands. The drafting machine yshown preferably comprisescounterpoise mechanismfor both sections 5f the parallel-motion arm. .Asuit-- able counterpoise v mechanism is lshown and claimed in our@pending-application.SerialKNO. 555,267 nowPatent-12,l552,335grantedMayfSf-IQE'I,

` tegral with a bracket I2 forming a part of the anchor assembly, whichbracket is adapted to engage over the upper edge of a drafting board orthe like D and be detachably xed thereto by a pair of clamp screws.

The anchor strut C comprises yokes or yoke portions or members 22, 23connected together and held in spaced relation with respect to eachother by tubular side portions or members 24, 25.

The upper yoke 22 is pivotally connected to a vertical bolt or pin xedin a boss formed integral with a web of the anchor bracket I2. As shown,the pin is held in position by suitable jamb nuts threaded onto thelower end and the head of the pin is enclosed by a member 3| threadedinto a tapped aperture in the center of the yoke 22. The construction issuch that` the anchor strut C is supported for rotation about the centerof the anchor band Wheel as an axis. The lower yoke 23 is pivotallyconnected to the band wheel -member at the elbow of the arm for rotationabout the center of the lower band wheel as an axis by a bolt or pin towhich it is connected by anti-fric; tion bearings.

The strut C is expandable or adjustable Yin length and separableintermediate the yokes 22, 23 to facilitate assembly and replacement ofthe band B and for the purpose of tensing the same, etc. To this end theside members 24, 25 comprise tubular sections 34, 35 and 36, 3j fixedlysecured to or formed integral with suitable bosses forming a part of theyokes 22,23, respectively. The adjacent ends of thetubular sections 34,35 and 35, 31 are normally held in spaced relation with respect to eachother and are operatively connected together by tubular nut-like members4|?, 4|, n respectively, the upper ends of'Y whichV are adapted toengage against shoulders formedV on members 42,' 43 V'fixed to the lowerends of the tubular sections 34, 35, respectively, while the whichengage within suitable apertures formed in the ends of the members 46.The construction affords a simple and convenient means for hooking theends of the band together and produces a band one end of which isextremely flexible and of minimum thickness, thus reducing to a minimumthe clearance necessary between the wheels and yokes to thread the bandabout the wheels. Obviously a band of any suitable construction may beemployed.

The protractor section F of the parallel motion armV is similar inconstruction and will not be described in detail. ,It comprises a pairof equal diameter band wheels encircled by a band similar inconstruction to the band B previously described and held in spacedrelation by a strut G comprising yokes 52, 53 located at the elbow anddrafting or protractor head, respectively, of the drafting machine andheld apart by side members 54, 55 similar in construction to the sidemembers 24, 25 previously described. The band Wheel at the elbow of theparallel motion arm is formed integral with the lower portion of theband wheel member of the anchor section A located at the elbow of thearm and the band wheel at the drafting head is formed integral with theholding ring of the drafting or protractor head. The yoke 52 of theprotractor strut G is supported by an anti-friction bearing for rotationabout a pivot lower end of the bolt or pin at the elbow of the arm andthe band wheel at the drafting head is rotatably supported by ananti-friction bearing in the yoke 53.

The protractor or drafting head shown' and referred to generally by thereference character H comprises a ruler assembly J including thenormally rotatable element K of the protractor proper, and one or morerulers 59. In addition, the protractor head comprises a normallyYstationary protractor element which stationary protractor elementcooperates with the rotatable Y protractor element to indicate theangularV posiother ends thereof Vare threaded upon the`enlarged upperends `of the tubular sections 36, 31. The'fact that theends ofthe'members 35, 3T1i'pon which the members 4o. 4|' are threaded Vareenlarged, permits the members 4|), 4| to 'be 'retracted over the tubularsections by rotating the former in a direction to move them to the leftas shown in Figs. 2 and 3 until the threads are disengaged andthereafter the tubular nut members will slide freely on the tubularsections. The tubular nut-like members 40, 4| are normally held inposition by jamb nuts 44, 45, respectively.

From the construction described above, it will be apparent that thelength of the strut C can be varied by adjusting or rotating theYtubular nut-like members 4D, 4| after first loosening the jamb nuts 44,45, and that when the nut-like members 4U, 4|V are retracted from theirnormal position, the flexible band B will be loose on the Wheels I0 andH with a considerable portion thereof exposed, thus facilitatingassembly or replacement of the band. Since the'sidemembers '24, 25 areof tubular form, the band B must be threaded through the strut and aboutthe wheels and is, therefore, made separable at one point.

-shown in Figs. -3 and 4,- one end of the band B isprovided with twospring members or armsv tion of the ruler or rulers with respect to somegiven base or reference line. The ruler assembly J is adapted to beindexedV relative to the Vstationary protractor element assembly L by anindex mechanism located, except for the projecting part of the thumbpiece 6| within and underneath the hand knob y62 also forming a part Vofthe ruler assembly. As shown the stationary protractor element L isprovided with a graduated circle and the rotatable protractor elementwith a reference or Zero line or Vernier. Alternatively the graduatedcircle may be placed onthe rotatable protractor element and the VernierAon the stationary protractor element, etc. Alterna- 'tively any desiredappropriate type of drafting or protractor head may be employed with theimproved parallel motion mechanismor arm of the present invention.

From the foregoing description of the preferred embodiment of theinvention, it will be apparent that the objects heretofore enumeratedand others have been accomplished and that there has been provided anovel and improved drafting machine or the like comprising a parallelmotion mechanism of the wheel and band type which is light in weight,rigid in construction and operation and of limited size and wherein thebands are completely enclosed but :canbelreadily reais-raars s placedand the tension 4thereof adhj'iisted as `'desired; v 4 While thepreferred embodiments of the invention have been described withconsiderable de'- tail, alternative constructions 4may beemployed.

lcomprising a strip 'or ribbon Vhearing Aits `ends 'connected togetherbetween said'vvheeis, va striit pivotally associated with said wheelsfor` maintaining the same in Vspaced relation with 'the band undertension and having twoaligned tub'u'- lar side members enclosingportions fof sai'diband between said wheels including portions adjacentsaid connected ends, and asleeve-like member surrounding a portion ofVsaid band and movable along one of said tubular side members andmovable `to and from the other of saidside members to afford access tosaidlends of said band.

2. In a drafting machine or thelike -a pair of band Wheels, a bandencircling said wheels and comprising a strip or ribbon having its endsdetachably connected together' between said'whe'els, and a strutpivotally "associated with said wheels `for maintaining the sainein'spac'ed relation' with the lband under tensioii land 'comprising twoaligned separable tubular side members 'enclosing portions of said bandadjacent said 'detachably connected ends, a sleevel'ine'fnber\'siirir'ii'nding a portion of said band and movable along'one of said tubular members into 'and'out of'eng'a'gement with theother of 'said tiibilar Irieinbers'to afford access to said detachablyconnected ends of said band.

3. In a drafting machine or the like, a pair of band wheels, a bandencircling said wheels and comprising a strip or ribbon having its endsconnected together, and a strut pivotally associated with said wheelsfor maintaining the same in spaced relation with the band under tensionand comprising two aligned separable tubular side members enclosingportions of said band adjacent its connected ends, and a sleeve-likemember surrounding a portion of said band and movable along one of saidtubular side members in one direction into engagement with the other ofsaid tubular side members to separate said side members to tense saidband, and movable in the opposite direction from said other tubular sidemember to afford access to said ends of said band.

4. In a drafting machine or the like, a pair of band wheels, a bandencircling said wheels and comprising a strip or ribbon having its endsthereof detachably connected together between said wheels, detachablesecuring means attaching said ends together, and a strut pivotallyassociated with said wheels for maintaining the same in spaced relation`with the band under tension and comprising two aligned separabletubular side members enclosing portions of said band adjacent to saidsecuring means, a sleevelike nut member adopted to be threaded on one ofsaid tubular side membersV and movable relative to the other of saidtubular side members lin one direction along said one tubular sidemember 'to afford access to said secu-ring means Vand in the oppositedirection along said cine Etubular side member -to moveagainstsaidsecond tubular member to -tense Isaid band.

5. In a strut adapted to vfor'rn a p'art of'fa drafting machine or thelike of the Wheel and -band type and hold the -band wheels thereof inspaced relation while encircled by lan endless band, two alignedseparable tubular side -fme'm'- bers adapted to enclose portions of theband extending between the wheels, and a sleeve mem- `ber surrounding aportion of -said band fand movable along one of -said tubularside-members into and `out of engagement with the other tubular memberto separate 'said tubular mein'- bers and to afford access to said band,respectively.

6. In la strut for a drafting machine or the 4like having a pair of bandwheels and v"a Aband encircling said wheels, the combination of twoaligned separable tubular side vmembers enclosing portions of said bandbetween said wheels-land `a sleeve-like member movable in oppositedirections along one of said tubular side 'mein-bers and adapted toslidably telescope with thef'othe-r of said tubular members Vwhen Vmovedyin'ori'e idirection and to be withdrawn with said other tubular memberwhen moved in the other' `'direction to alford access to fsa'id band.

7. In a strut adaptedfto'form a partof 'adr'afting machine `or the likeo`f the wheel and fband type and hold the band wheels thereof in spacedrelation while encircled by a band, Y-thecembinationv of two alignedtubular side members adapted to enclose "portions of the band entendingbetween the vwheels anda sleeve-like mempber Yadjustably positioned onone of said 'tubular side vmembers and movable relative thereto in onedirection to engage the other of said tubular side members to'ur'ge saidtubular Vmembers :from one another to extend the strut and tense A'saidband, and movable in the opposite direction and from said other tubularmember to afford access to said band.

8. In a drafting machine or the like having a pair of band wheelsencircled by a band, and

ra strut pivotally associated with said wheels for maintaining the samein spaced relation With the band under tension, said strut comprisingtwo aligned tubular members enclosing portions of said band between saidwheels, a sleeve interconnecting said tubular members and having one endportion slidingly telescoped with one of said tubular members and havinga part abutting said one member to urge it in a longitudinal direction,and means for adjustably attaching the other end portion of said sleeveto the other of said members to adjustably position said sleeve alongsaid other member for selectively spacing said members by said sleeve.

9. In a drafting machine or the like having a pair of band wheelsencircled by a band, and a strut pivotally associated with said wheelsfor maintaining the same in spaced relation with the band under tension,said strut comprising two aligned tubular members enclosing portions ofsaid band between said wheels, a sleeve for interconnecting said tubularmembers and having one end portion threaded on the end of one of saidtubular members and the opposite end portion slidingly telescoped withthe other of said tubular members and having a part abutting said othertubular member to urge it in a longitudinal direction when said sleeveis 'threaded outwardly on said one tubular member, said its ends greaterthan the diameter of the threaded 'end of said one tubular memberwhereby said sleeve can be movedonto said one tubular member and awayfrom said other tubular member to expose a portion of said band.

10. In a drafting machine or the like having a pair of band wheelsencircled by a band, and a strut pivotally associated with said wheelsfor maintaining the same in spaced relation with the band tension, saidstrut comprising two aligned tubular members enclosing portions of saidband between said wheels, a sleeve interconnecting said tubular membersand having one end portion slidingly telescoped with one of said tubularmembers, said one tubular member having an abutment thereon engaged bythe rend of said sleeve, and means for adjustably connecting the otherend of said sleeve to the other of said members to adjustably positionsaid sleeve along said other member to maintain said tubular membersseparated.

11. In a drafting machine or the like having a pair of band wheelsencircled by a band and a strut pivotally associated with said wheelsfor maintaining the same in spaced relation with the band under tension,said strut including two parallel tubular sections enclosing parallelreaches of said band, each section comprising two aligned tubularmembers, a sleeve interconnecting the spaced tubular members and. havingone end slidingly telescoped with one of said members and having a partabutting said one member to urge it in a longitudinal direction, andmeans for adjustably connecting the other end of said sleeve to theother of said members to adjustably position said sleeve along saidother member for selectively spacing said members by said sleeve.

12. In a drafting machine or the like having a pair of band wheels, astrut pivotally associated with said wheels for maintaining the same iiispaced relation, a separable band encircling said wheels, meansintermediate said wheels for securing separable ends of said bandtogether, said strut comprising two aligned tubular members enclosingportions of said band between said wheels, said aligned members beingspaced from one another opposite said means, a sleeve surrounding saidmeans and having one end slidingly telescoped with one of said tubularmembers and having a part abutting said one tubular member to urge it ina longitudinal direction, said sleeve telescoping at the other end withthe other of said tubular members and being movable therealong in onedirectionr to be withdrawn from said one tubular member to afford accessto said means, and means for adjustably connecting said other end ofsaid sleeve to said other tubular member to adjustably position saidsleeve along said other member for urging said tubular members from oneanother to tension said band.

CHARLES HENRY LITTLE. CHARLES HU'BBARD LITTLE'.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 249,909 Donahue Nov. 22, 1881428,046 Hanagin May 13, 1890 '793,325 Stiles June 2'7, 1905 '797,911Perry Aug. 22, 1905 1,902,038 McAllister Mar. 21, 1933 2,168,940 LittleAug. 8, 1939 2,243,732 Eubanks May 27, 1941 2,316,485 Langsner Apr. 13,1943 2,407,235 Halstead Sept. 10, 1946

